vA, 

a v x A Preliminary Report 

\ 

V 

ON THE 

Arkansas Diamond Field 


BY 


Philip F. Schneider, M. Ph. 


Issued by the 

Bureau of Mines, Manufactures and Agriculture 

GUY B. TUCKER, Commissioner 


CENTRAL PRINTING COMPANY 
Little Rock, Arkansas 
1907 

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i 


v/ 

























A Preliminary Report 


ON THE 

Arkansas Diamond Field 


BY 


Philip F. Schneider, M. Ph. 

I) 


Issued by the 

Bureau of Mines, Manufactures and Agriculture 

GUY B. TUCKER, Commissioner 



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4 


* * V 


CENTRAL PRINTING COMPANY 
Little Rock, Arkansas 
1907 


y 




Letter of Transmittal. 



I 


To His Excellency , X. 0. Pindall, Acting Governor: 

Sir— I have the honor to submit to you for publica¬ 
tion by the State, a preliminary report on the Arkansas 
Diamond Field prepared by Professor Philip F. 
Schneider, M. Pli. 

Much interest has been manifested throughout the 
country in the Arkansas diamond discovery and this 
office has been flooded with requests for information 
by capitalists and scientists from various parts of the 
world seeking reliable information. This we were 
unable to supply as the edition of Brunner’s report has 
long since been exhausted. It therefore became im¬ 
perative to have some official report prepared by a com¬ 
petent authority discussing in full the various details 
of the subject. 

This work lias been entrusted to Philip F. Schnei¬ 
der, of Syracuse, New York, a geologist of the highest 
repute and one thoroughly familiar with peridotite 
rock, who was instructed to visit the field, secure all 
the information possible, and embody the same with 
suitable illustrations and a complete discussion of the 
entire subject in a report to this Bureau for publication 
by the State. It is expected that this report will be 
ready for publication by the close of the year. 

The present bulletin is a preliminary account, 
which has been prepared to satisfy the immediate 
demand for accurate information. 

i * 

Respectfully, 

Guy B. Tucker. 

Commissioner Mines , Manufactures and Agriculture. 




6 If 
Ql 0 * 


j9 






JOHN WESLEY HUDDLESTON 


The Discoverer of the Arkansas Diamond Fields 






f 



The Arkansas Diamond Fields. 


Pike County, Arkansas, deserves the distinction of 
being the first American locality in which diamonds 
have unquestionably been traced to their rocky matrix 
of peculiar kimberlite, where they were either formed 
by nature or at least brought to the surface by the 
unexplained forces which aided in producing the same. 
In fact this State has long shared with New York and 
Kentucky the honor of being one of the three known 
American localities where this peculiar peridotite, 
sometimes spoken of as kimberlite, was found. 

While this rock was recognized and described 1 as 
long ago as 1889, it appealed only to a comparatively 
few persons, mostly scientists, to whom it was of in¬ 
terest because of its rarity as well as to the uncertainty 
regarding its origin. More than three-fourths of a 
centurv before the discoverv of the Arkansas dia- 
monds, and nearly half a century before these gems 
were first recognized in South Africa, Vanuxem 2 , one 
of the earliest of the American geologists, was puzzled 
by its peculiar character, and suggested an igneous 
origin for the New York serpentine (peridotite), which 
was the only one of its kind then known, nor has the 
question ceased to puzzle our best scientists since. In 
fact tfie formation of serpentine into which" this rock 
changes has ever been one of the vexed a nest ions of 
geology. It was not until 1887 that Dr. G. H. Williams 3 
satisfactorily proved the igneous nature of the Ameri¬ 
can varieties, Diller 4 describing the Kentucky peri¬ 
dotite, and Branner 5 the Arkansas variety, while the 
origin of the South African kimberlite is still in doubt. 

1 The Peridotite of Pike Co., Ark., fcy Branner and Brackett. Am. Jr. Sci.. 

1889. 

2 N. Y. State Geol. Repts., 1838-1842. 

3 Science, March 11, 1887; Am. Jr. Sci., XXXIV, 1887; Bull. Geol. Soc. 
Amer. I, 1890. 

4 Bull. Geol. Sur., No. 38; Am. Jr. Sci., XXXII, p. 121; Science, 18&5, 
p. 65; Am. Jr. Sci., Oct., 1 892. 

5 Am, Jr. Sci. XXXVIII, 1889, p. 50; Ark. Geol. Sur., An. Rept., Vol. II, 

1890. 


5 




It was quite a few years, however, after the dis¬ 
covery of the South African diamonds in the peridotite 
pipes and dikes before its resemblance to the American 
rocks was first noted and the remarkable similarity in 
structure, in inclosures, in eruptive character, and in 
chemical composition of the rocks of these widely sep¬ 
arated localities, fully described. 0 Naturally this re¬ 
markable similarity suggested the possibility of dia¬ 
monds being found in this rock at all of these localities, 
but strange to relate, at only one of the localities * 7 8 was 
any search made for the gems. At the other two local¬ 
ities, namely in Arkansas and in New York, no one 
evidently was sufficiently interested to even consider 
the magnificent possibilities indicated by science along 
this line, and it was left for Mr. John Wesley Huddle¬ 
ston, a native of Arkansas who knew absolutely nothing 
of these profound investigations of the scientist, or of 
the possibilities of the kimberlite as a prospective dia¬ 
mond mine, to find the first unquestioned diamond in 
this rock in America, thus attracting the attention not 
only of the scientist but of the ordinary person as well 
to this subject, and making diamonds, peridotite, kim¬ 
berlite, Murfreesboro, Pike County, and Arkansas, all 
household words throughout the country. 

LOCALITY. 

The locality where this rock occurs is a somewhat 
restricted area lying about two and one-lnalf miles 
southeast of Murfreesboro. The rock is first noticed 
in the hillside about 400 yards east of Prairie Creek, 
near its junction with the Little Missouri River. 

The occurrence of this peculiar mass of igneous 
rock, which differs so materially from the sands and 
gravels of the river valley through which it rises, could 
scarcely fail to attract the attention of even the most 
casual observer. It was mentioned by PowelP as far 
back as 1842, as well as by several other of the early 
scientific writers, and as already stated has been 
described in detail by Branner and Brackett in 1'889. 

0 ‘‘The Genesis and Matrix of the Diamond,” H. C. Lewis, 1887. 

7 The surface conditions in Kentucky were regarded as so favorable for the 
formation of diamonds by the action of heated rock upon the Carbonaceous 
shales through which it passed that there has been some search for diamonds 
in that locality ever since the theory was suggested, about twenty years ago. 
While two diamonds are known to have been found in Kentucky, they cannot 
positively be referred to the peridotite. 

8 Geol. Rept. on Fourche Cove, 1842. p. 6. (See Branner.) 

6 



THE IGNEOUS AREA. 

The igneous area composed of the rock is roughly 
elliptical in form and is given by Branner as 2,400 by 
1,600 feet in extreme dimensions, and extending in a 
general northeast and southwest direction. It is quite 
probable, however, that a minute examination of the 
locality would prove that it is even more restricted 
than this, as the southwest hill contains but little peri- 
dotite upon the surface, being composed of a greenish 
colored quartzite and drab sandrock which have here¬ 
tofore been referred to the Carboniferous age. 

The two remaining hills which form a large part 
of the igneous area are locally known as the east and 
west hills, but in order to avoid any confusion as to 
whether the west hill, composed of the Carboniferous 
quartzite, or the locally named west hill, which is 
composed of the peridotite, is meant, the latter will be 
spoken of as the central hill. 

These hills, which rise from sixty to eighty feet 
above the level of the valley, form a ridge which slopes 
steeply to the north and west but inclines more gently 
toward the Little Missouri on the south. The northern 
slopes of the hills are largely made up of the harder 
masses of the peridotite which lias weathered out into 
boulders of various sizes. 

The east hill has a cap of Carboniferous sandrock, 
which covers nearly all of the top. On the north and 
especially upon the west side it has a talus of the 
smaller boulders which are slowly decomposing, to¬ 
gether with more or less of the decayed and disinte¬ 
grated yellow earth, which is merely the decomposition 
product of the peridotite. 

A spur of the hard peridotite extends slightly 

west of north from this east hill, and is exposed for 

a distance of about twentv feet in the south bank as 

•/ 

well as in the bed of the Poorhouse Branch. In ap¬ 
pearance this spur of the peridotite is not greatly dif¬ 
ferent from the slightly decomposed peridotite of the 
other localities, its interest lying in the fact that it has 
not previously bee n reported as occurring in this branch. 
In fact all the known references to the branch distinctly 
state that it contains no exposures of the peridotite. 

It will also be of interest to note that the decayed 
earth and sand at this particular locality show many 

7 


beautiful bright green crystals of olivene. Some of 
them are exceedingly clear and brilliant and should a 
careful examination of the soil and rock prove that 
equally well preserved crystals of this same brilliant 
shade and of a size suitable for cutting occur, they will 
make especially tine marketable gems. 

The central hill contained none of the Carbonif-* 
erous sandrock so prominent upon the other two hills, 
but appeared to be made up entirely of a compact, dark- 
colored, massive peridotite, showing little alteration by 
the weather. The rock, however, has broken and split 
up into large blocks and boulders, a few iof which have 
rolled down the slope toward the bottom. The fact that 
so few of these blocks have been displaced suggests 
that these cracks and breaks are reallv the fractures 
produced by the cooling of the heated mass, subse¬ 
quently effected by the various atmospheric agencies. 

Toward the south, except in the very midst of the 
hill slope, the surface inclines almost imperceptibly 
toward the river. That portion of this area which lies 
nearest the ridge is composed of a much decomposed 
peridotite. This condition is very clearly shown in the 
beds of the two small wet-weather streamlets, which 
have their source in the diamondiferous area, and flow 
southward across and through the sands and gravels of 
the river valley and empty into the Little Missouri. 
In the channels of these streamlets the decayed peri- 
- dotite is covered by a thin layer of black gumbo-like 
soil, averaging not more than a foot in thickness to¬ 
gether with some pebbles undoubtedly obtained from 
the adjoining conglomerate. Beyond the observed 
igneous area these streams show that the river flat is 
made up of about four feet of yellowish sand over a 
cemented gravel showing about three feet thick but 
which other excavations prove to be from ten to twenty 
feet thick. 


METAMORPHISM. 

The adjoining sandstones show only slight traces 
of metamorphism due to the intrusion of this heated 
maiss. In fact the dip of the rocks on the west hill, and 
the capping of Carboniferous rocks on the east, to¬ 
gether with the structure of the peridotite itself seems 

to indicate that the entire mass was covered at least in 

8 


large part by the Carboniferous rocks, and then subse¬ 
quently eroded, although it would be difficult, if at all 
possible, to prove this contention, even by considerable 
excavation. 

The very slight amount of metamorphic change is 
further shown by the contact of the peridotite dike at 
the mouth of Prairie Creek with the soft Cretaceous 
sandstone. Outside of a slight darkening of the color 
of the adjoining sandstone for about an inch on either 
side of the dike there is practically no metamorphic 
change. It is true that this adjoining material is some¬ 
what softer than the remainder of the Cretaceous for¬ 
mation, but this is readily explained by the ease with 
which the atmospheric agents would penetrate the 
fissure and attack the rock. 

THE PERIDOTITE. 

The Arkansas peridotite, or diamond bearing rock, 
in unweathered 'specimens is a dark green, almost a 
black rock, of dense texture, and containing numerous 
sparkling particles of black mica (biotite). Freshly 
broken pieces also show what seem to be jet black crys¬ 
tals imbedded in the mass of the peridotite, but in 
thin sections these crystals appear to be of a dark 
green color. These crystals and grains of olivene make 
up the greater portion of the mass. 

Specimens of the peridotite which are somewhat 
decomposed, however, become a dark yellowish brown 
color, the olivenes changing to decidedly yellow colored 
masses which show very prominently in the darker 
ground mass. The mica apparently is but slightly 
affected by the weathering agencies. 

Where decomposition has gone on to a consider¬ 
able extent the rock breaks up into a mass of more or 
less angular fragments, which in the later stages change 
to a soft friable more or less earthy mass of a decidedly 
yellowish or greenish yellow color. As already stated 
this greenish yellow earth covers the greater portion of 
the igneous area south of the ridge of hard peridotite, 
and is of special interest because it comprises that 
portion of the igneous mass in which the diamonds 
have all been found. Whether this badly decomposed 
mass of the peridbtite is merely a part of the same 
which breaks up more readily than does the harder 

9 


material of the ridge of hills to the north, the writer 
is not prepared to state, not having examined this part 
of the field, but there is little question but it is. How¬ 
ever, it must he borne in mind that a part of this 
decayed material may have been washed down there 
from the hillsides, which partly surrounded it, to the 
north and west. 


MINING THE GEMS . 

A large number of the gems discovered up to the 
present time have been picked up by the workmen upon 
the surface, usually after a rain. About a week ago, 
during the writer’s sojourn at the field, a handsome 
canary diamond of about two carats weight, a perfectly 
formed hexoctaliedron, was thus picked up by one of 
the guards 9 outside of the inclosure. He was not 
searching for gems particularly at the time but hap¬ 
pened to notice a gleam of light flashing from the 
ground about twelve feet ahead of him, he went to the 
spot, and picked up the diamond. 

Shortly before this another guard, Mr. Jim Key, 
while sitting upon a mass of the rock eating his lunch, 
happened to glance down and noticing a bright sparkle 
in the rock, took out his jack-knife and began to pick 
and cut away the rock, and presently had picked out 
from its matrix a half carat diamond. It was unfor¬ 
tunate that this gem was taken out from its resting 
place. However, the owner of the mine told me of 
another stone which was found and only partly sep¬ 
arated from the inclosing rock, thus proving beyond a 
doubt the existence of the diamond in the peridotite. 
This interesting specimen was not in the possession of 
the owners at the time of my visit, and could not be 
seen, although a photograph of the same was shown. 

However, some of the gems are obtained by wash¬ 
ing the rock, after the manner of the South African 
diamond companies. In brief the method employed 
is as follows: 

The peridotite, because much of it is already in the 
decomposed disintegrated state, does not need at pres¬ 
ent to be exposed in order to permit it to> break up as 
in South Africa, although about six acres has been 
plowed up and is virtually being reexposed to the at- 


9 Mr. Lee Wagner. 


10 



mosphere. This material is next taken to the concentra¬ 
tor, or washing machine, where it is mixed with water 
and agitated by rapidly revolving arms fitted with iron 
teeth ftor the purpose of carrying off the earth and 
lighter material, while the diamonds with the heavier 
stones and pebbles settle at the bottom. From time 
to time these are drawn off and screened through one- 
half and one-quarter inch mesh sieves which separate 
the larger rocks and fragments from the rest. These 
concentrates are then spread out upon a table and care¬ 
fully sorted over to obtain the diamonds which they 
contain. 

The grease separator which has proved so valuable 
an adjunct to the African mining companies for obtain¬ 
ing the gems from the other concentrates has not as 
yet been tried by the local company, although Mr. John 
Peay, the manager, has been experimenting along that 
line with some success. The great lack of the company 
at the present time is water. However, a pumping 
plant, with a capacity of 97,000 gallons will shortly be 
installed upon the banks of the Little Missouri, which 
should give them a plentiful supply of water. 

THE DIAMONDS. 

Up to the present writing, October 14, 1907, over 
one hundred and sixty diamonds have been found. 
More than fifty of these gems, all that were in the 
possession of the owners at the time of the writer’s 
visit, were shown to him and drawings and descriptions 
of the same made. These will be given in full in the 
final report. The remainder of the stones, which are 
said to represent by far the better part of the ma¬ 
terial, were sent to Mr. George F. Kunz, the most dis¬ 
tinguished gem exoert in America, for examination and 
description. In his report , 10 he says: 

‘‘About 130 diamonds have thus far been found, 
the weight varying from 3 1 2 of a carat to 6 V 2 carats. 
The first stone found by Mr. Huddleston is white and 
weighs 4% carats; the second, also white, weighs three 
carats; the third is yellow and weighs % carat. The 
majority of the stones are flattened octahedrons; some 

10 “The Arkansas Diamond Field,’’ Kunz & Washington. Special Rept. in 
U. S. Mineral Resources for 1906. Section on Precious Stones. 


11 



are flattened and triangular, and a few are almost 
perfect octahedrons. No cubes have been found. Most 
of the stones are white, a large proportion being of good 
water, and the white of exceptional purity, finer than 
most African stones. A smaller number are brown, 
some are yellow, and several small individuals are 
bort. ” 

The stones examined by the writer could scarcely 
be designated iais representative material from the mine, 
and were interesting scientifically rather than economi¬ 
cally, the following facts being especially noteworthy. 

(1) The tendency of the crystals toward the ca¬ 
nary shade of color, although some very good white 
crystals were seen. 

(2) Crystals triangular, much flattened or elon¬ 
gated, and a preponderance of the liextetraliedral form. 

(3) The peculiar markings, or corrosion, of the 
surface of quite a number of the crystals. In fact 
some (of them appeared as though they had been im¬ 
mersed after formation in some substance capable of 
dissolving or corroding the carbon. One of the crystals, 
probably a rhombic dodecahedron, was so acted upon 
in this way that its sharp edges were entirely destroyed 
and eaten away, making the determination of the crystal 
form almost impossible. These forms were suggestive 
of Herr Luzi’s 11 experiments and indicate the possi¬ 
bility of more than one eruption. 

(4) One slightly distorted octahedron appeared 
somewhat milky, and when examined carefully with 
the glass showed that its entire surface was studded 
with numerous hexagonal pittings, in much the same 
way that the inverted triangles appear on many 
African stones. 

These facts, together with others indicating a pos¬ 
sibility of carbonado occurring in the workings, will 
be taken up more fully in the final paper. 

OTHER GEMS . 

The pyrope garnet, or “Cape Ruby,” which oc¬ 
curs so abundantly in the Kentucky peridotite, and 
more sparingly in the New York and South African 
rocks, is quite small and very rare in the Arkansas 

11 “Artificial Figures of Corrosion on Rough Diamonds,’’ Berichte der 
Deutschen Chemischen Gesellschaft, 1892. 

12 



peridotite. Mr. Huddleston is authority for the state¬ 
ment that about sixty were found among the heavier 
concentrates from the material washed at the river. 
One round garnet, of the usual red color, was shown to 
the writer with one of the packages of diamonds. 

As to the ilmenitte, it has been said that this 
mineral has not been found in the Arkansas peridotite, 
but several pieces were shown to the writer by one of 
the members of the company to whom they were sent 
in the belief that they might prove of value. 

The clear-green crystals of olivene have been de¬ 
scribed. 


GENUINENESS OF THE FIELD . 

Because 'of the uncertainty connected with the 
entire subject, caused in part at least by the reports 
of certain so-called experts, who were denied admission 
to the field, and therefore had no hesitancy about pro¬ 
nouncing the find a “fake” and a “salt,” as well as to 
the suspicion with which capital naturally regards any 
new mining enterprise, we were instructed to lay special 
stress upon the subject of the genuineness of the field. 
While the writer was shown many of the little courte¬ 
sies by the company which scientific men are so accus¬ 
tomed to receive that they have come to regard them as 
their right, nevertheless lie was refused permission for 
the present to visit the six acres of productive diamond 
ground. However, he is convinced from innumerable 
facts, no one of which is conclusive, but which taken 
together are too strong to be refuted, of the absolute 
genuineness of the find. Here are a few of the reasons: 

(1) The occurrence here of the kimberlite, or 
diamond-bearing rock, which is the most natural place 
for the diamond to be found. 

(2) The 165 unquestioned diamonds, which can 
actually be shown, and said to come from this place. 

(3) The probability that they did come from this 
field, as they possess peculiarities both of crystal form 
and color, showing a marked family resemblance which 
would hardly be true for a collection of rough stones 
bought in open market, and which misrht have come 
from several mines. In fact, these family traits in the 
gems are such that only a speculator of exceptional 
ability and knowledge of the occurrence of diamonds 

13 


would understand and have the prudence to search 
for, in purchasing a parcel of gems f.or “salting” pur¬ 
poses. 

(4) The straight-forward story told by Mr. Hud¬ 
dleston, the discoverer of the diamonds, which is so 
simple and unvarnished a tale, and so convincing in 
its completeness, that it will be given verbatim in the 
final report. 

(5) The comments of the people of that vicinity 
and of former workmen iof the company all favor the 
finding of the diamond. None of these people doubt, 
or even question, the finding of the gems. 

(6) The character and reputation of the men com¬ 
posing the company, men who could not afford to jeop¬ 
ardize their standing in the community by association 
with any questionable concern. 

(7) The finding of the gem in the matrix, where 
it still remains as vouched for by Dr. Kunz, who is far 
too experienced a hand to be misled in such a matter. 

(8) The methods employed by the company to 
develop the mine. They are not “selling stock on a 
mere speculation,” or “get rich quick” plan, but doing 
the most reasonable thing under the circumstances— 
cautiously developing the property until such time as 
they are convinced that the yield of gems will pay for 
mining on a large scale. 

However, enough reasons have been enumerated 
to prove conclusively the occurrence of the diamonds. 

PRODUCTION. 

Are the conditions such that Arkansas will become 
an important factor in the diamond production! 

About 160 diamonds have been obtained during 
the past year from about six acres by a few workmen 
with crude machinery, working only a small portion of 
the time because of lack of water. This would seem 
to indicate an extremely productive field, but is it! 
Situated as they are, the six acres have for centuries 
received the wash of the three hills to the north, acting 
as a natural concentrator, and the gems which are 
apparently found in such abundance may be the accu¬ 
mulations of a thousand years in this particular spot. 
However, I do not wish to be understood as belittling 
the possibilities of the field, but merely suggest a rea- 

14 


son for its surprising surface productiveness, and one 
which must be taken into consideration in determining 
its true value. 

To properly do this, enough of the rock, say a 
few thousand loads, should be carefully washed, 
screened, and sorted, and an accurate account kept of 
the number and weight of the diamonds found therein, 
for determining the actual percentage per load. 
With this as a basis it will not be difficult to determine 
the actual cost of production and to discover whether 
the gems can be profitably mined. 

Another and a very serious factor will enter into 
the problem, namely, the depth of the yellow disinte¬ 
grated peridotite, and whether the harder blue ground 
beneath will become decomposed in a reasonable length 
of time, thus permitting the diamond to be won. Should 
this not result, some economical way must be devised 
for treating the rock, causing it to disintegrate, other¬ 
wise the very richest diamond-bearing ground would 
be valueless. 


OTHER FIELDS. 

The question naturally arises, Is this the only dia¬ 
mond field in the State? While it is possible that there 
are other occurrences of the diamond-bearing perido¬ 
tite in Arkansas, it is quite unlikely, otherwise with 
the interest manifested, the search now being carried 
on, and the survey work already performed, they would 
doubtless have been brought to light. However, this 
supposition may be proven fallacious any day by a 
second Huddleston actually bringing in some diamonds 
from a new locality. At present none such is known, 
certainly not in close proximity to the mine. 

The Little Rock Diamond Mining Company was 
sufficiently farsighted to acquire practically all of the 
known peridotite outcrop, only a small portion of the 
same being in other hands. Should any diamonds be 
found (not in the peridotite) on the adjoining prop¬ 
erty, they will be mere floaters and will not occur in 
quantity sufficient to pay for searching. The river 
gravels below the igneous outcrop are more likely to 
contain a few stones but even here they probably do 
not exist in quantities sufficient to pay for carrying on 

a continuous search for the same. 

15 


Does the peridotite occur in the immediate vicinity 
of the outcrop, but hidden by the overlying Tertiary 
gravel? This it is impossible to state without sinking 
innumerable pits, or drilling through the overlying 
sands and gravel everywhere. Then it would be proven 
only for the places actually tested. With one excep¬ 
tion none of the wells which penetrate the gravel show 
the peridotite, although several cut into a greenish 
marl and quartzite. The exception is a well sunk near 
the cabin standing just north of the place where the 
Poorliouse Branch crosses the Washington road. This 
is about 650 yards northwest of the central hill. The 
few pieces of the peridotite lying near this well are 
just as likely to have been brought there from the 
neighboring hill by some former inhabitant of the now 
vacant cabin, as to have come from the excavation. 

In conclusion we can merely repeat that Pike 
County lias a genuine diamond mine, but its probable 
value cannot, even be estimated until after hundreds of 
tons more of the rock have been thoroughly screened 
and sorted, the actual percentage value of diamond per 
ton ascertained, and the decomposing factor of the 
harder 4 ‘blue ground” actually determined. 


1(5 











